A double dose of Delphinium advice

Q: The flowers have faded on my Delphinium and the plant is beginning to look tatty. Can I cut it back without harming it?

A: The brilliantly colored flower spikes of Delphiniums make bold, long-lived additions to the mixed border, but you need to take immediate action to encourage your plant to bloom a second time.

As soon as the flowers fade, cut the flower stalk to lateral buds immediately below the spent flower. The secondary flowering branches will be much smaller and less showy, but are perfect for flower arrangements.

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After the secondary flowering is complete, cut all of the stems down to newly developed foliage at ground level. You will have a noticeable void in your garden, so encourage the plant to grow back rapidly by working a mixture of 2 cups of alfalfa meal and a cup of organic-flower food into the soil around the plant. Mulch with compost and water as necessary to make sure the soil remains evenly moist.

If all goes according to plan, your Delphinium will quickly fill in the void and will rebloom by late summer.

Q: How do you stake Delphiniums? I stake them, but they always end up floppy.

A: I used to share your frustration with staking Delphiniums. I’d have so many stakes and ropes tied around them, they looked like hostages in the front yard; yet despite all of my efforts, the whole clump would fall over after the first rainstorm.

My frustration ended when I discovered circular- grid supports. Available at most nurseries, circular grid supports consist of a wire ring filled with a pattern of cross wires, supported by stakes that sink into the ground.

The secret to success is to set the system up early enough in spring to allow the stems to grow up through the grid. Setting it all up can be a bit tricky. It’s difficult to get the support wires situated correctly so the circle ends up level and centered over the plant.

Once the stems grow through the grid, however, it does a great job of holding the plant upright. I’ve yet to have a clump fall over since I began using this system a few years ago. Best of all, once the stems grow through it, the foliage totally hides the staking system.

Make sure to collect and store the circle grids and support wires at the end of the season. I left a couple out in the garden over the winter a couple of years ago, and I’m still searching for a few of the support wires that are still out hiding in the garden.